The latest news about fertility at every age

Just when you're leaning in to your life, you can start hearing it in the distance: the drumbeat of fertility anxiety. Your drive and ambition could be earning plenty of wins, but people still whisper that your biological clock is ticking and your ovaries are shriveling, so if you don't lock down a baby daddy and procreate before your early 30s, you might never be able to.

No surprise, then, that so many smart women wonder whether taking the time to meet the right partner could be dooming their wombs. In fact, 40 percent of women ages 18 to 40 in a new Yale School of Medicine study said that if they were trying to get pregnant, they'd be concerned about whether they'd be able to conceive.

But according to new research, that mounting fear about our ability to conceive just may be unfounded, stoked by a news cycle determined to fan the flames.

"Your fertility is a finite thing, and you need to be aware of this. But these days, fertility obsession has taken over," said Dr. Hilda Hutcherson, professor of obstetrics and gynecology at Columbia University College of Physicians and Surgeons. "I see so many young women in my practice, even in their early 20s, who are already alarmed about whether they'll be able to have kids. Most of my younger patients have no reason to worry."

That's reassuring news if you're currently hitting your stride in your career and can't easily switch to motherhood mode or if you haven't yet met the partner you want to make babies with. So take a collective deep breath. Take a look at the science and learn more about why you really can dial back the baby mania.

Is 35 the fertility cliff? Even women who are years away from their 35th birthday have it burned in their minds that it's all downhill from there.

"I've always heard that getting pregnant becomes more difficult after 30, and at 35 fertility really takes a dive," said Claire H., 28, who has been dating a new guy for about 10 months. "I know I want kids, so I've been doing the math—dating, engagement, time to just be married, the time it might take to conceive, plus the actual pregnancy—and I'm already behind the curve."

But is she really? When you look at the numbers, the time line is likely fine. A 2013 study from Fertility and Sterility determined that 78 percent of 35- to 40-year-olds became pregnant within a year, compared with 84 percent of women between 20 and 34, if both groups had sex during the most fertile time in their cycles. Instead of a plunge, the fertility cliff may more closely resemble a bunny slope.

This reinforces an earlier study of 782 couples by the National Institute of Environmental Health Sciences, which found that the difference in fertility rates between women heading into their mid-30s and women looking at 40 was just 4 percentage points: Eighty-six percent of 27- to 34-year-olds who had sex twice a week were able to get pregnant naturally within a year, versus 82 percent of 35- to 39-year-old women.

That's not to say age doesn't matter—it definitely does. You're born with all the eggs you'll ever have—about 1 million. Each year, thousands die naturally, so by puberty, you're at 300,000, and the numbers continue to decline. And the younger the egg, the less likely it will carry abnormalities that prevent it from developing into a healthy embryo. Still, the overall risk for these complications remains low.

The most pronounced drop in fertility happens after 40, reproductive specialists say.

"Your chance of conceiving at age 42 is about 9 percent per cycle," explains Dr. Pasquale Patrizio, a fertility researcher, clinician and director of the Yale Fertility Center. "By 44, it's 2 percent per cycle, and at 45, it's at most 1 percent per cycle."

This isn't to say that conception won't happen—women in their early 40s have healthy babies naturally all the time, said Dr. Mary Jane Minkin, clinical professor in the department of reproductive sciences at the Yale School of Medicine. But biology isn't on your side.

So if hitting 35 doesn't mean your baby-making days are absolutely over, how did it get stuck in women's heads? It might be linked to the fact that the chances of having a baby with a genetic abnormality do increase at that point. When giving birth at age 25, the risk of having a child with Down syndrome, for example, is one in 1,250; at 30, it's one in 1,000; at 35, it's one in 400. The increased risk isn't hype, but "even that is small in real life," Dr. Hutcherson says. That means you have a 99 percent chance of having a baby without Down syndrome.

The Problem May Not Be You
All the news spotlights the trouble that women can have with fertility, leading them to consider drastic (and often premature) solutions, while men's fertility issues go largely unreported.

"Women tend to worry about fertility much more than men, and if they do have trouble conceiving, they're the ones asking, 'What's wrong with me?'" Dr. Hutcherson said.

But the fact is, for about 40 percent of the couples unable to conceive, the guy is either the sole cause of the problem or at least a contributing factor. Usually, male infertility is triggered by low sperm counts or poor sperm quality. It can also be the result of age or even lifestyle factors like smoking and drinking.

We're led to believe that women need to panic about their age while men can father perfect babies anytime, but that's not the case. Even if men have no issues fathering children, paternal age may be associated with a higher rate of psychological disorders and developmental conditions like autism. A JAMA Psychiatry study from 2013 found that kids born to men over 45 were 3.5 times more likely to be diagnosed on the autism spectrum and 13 times more likely to be diagnosed with ADHD than those born to the same men when they were 20 to 24.

Finally, Egg Freezing Got an UpgradeConsidered experimental by the American Society for Reproductive Medicine until 2012, egg freezing has become a more viable possibility—thanks to increased use of a relatively new technique that "flash freezes" eggs to help preserve their structure. The newer process, called vitrification, freezes the eggs so fast that ice crystals don't form and cause damage as they did in earlier techniques.

The age of your eggs is important, too, said Dr. Elizabeth Fino, reproductive endocrinologist and infertility specialist at the NYU Fertility Center in New York City. Women who choose to freeze their eggs before age 35 have about a 45 percent rate of live births at Dr. Fino's clinic. By the time a woman is 40, the success rate falls to 37 percent, she said.

Another factor to keep in mind: If you're ready to go for it, you'll need to plan for the hefty expense. It can cost up to $12,000 to harvest and freeze your eggs, then at least $500 a year for storage, and elective treatments aren't covered by insurance.

"But you can make sure that when you're ready to have a baby, your body will be ready, too," Patrizio said.

Maintaining a healthy weight is especially important. Women with a body-mass index below 19 generally have too little body fat to sustain a pregnancy, and their bodies put the brakes on ovulation, so conception can't happen, Minkin said. Being seriously overweight can also put a dent in fertility, but carrying 10 or even 20 extra pounds won't affect it.

And here's yet another reason not to smoke: Even the occasional cigarette might make your eggs more prone to chromosomal abnormalities. Also, don't postpone yearly ob/gyn checkups, and be honest with your M.D. about symptoms like irregular bleeding or pelvic pain. They could be tip-offs to treatable conditions such as endometriosis or uterine fibroids, which could impair your fertility if left unchecked.

Managing stress (including fertility stress) could also be a good idea.

"Some evidence shows that stress can delay conception when you're trying to get pregnant," said Alice Domar, director of integrative services at Boston IVF. Learn to dial it down now with deep breathing, mindfulness practice or yoga, skills you'll definitely need when you're ready to become a mom.